Bump actions/cache from 3 to 4

Bumps [actions/cache](https://github.com/actions/cache) from 3 to 4.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v3...v4)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/workflows/docs-test.yml

@@ -26,7 +26,7 @@ jobs:
           python-version: '3.10'
 
       - name: Cache pip
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # this path is specific to Ubuntu
           path: ~/.cache/pip

.github/workflows/flake8.yml

@@ -23,7 +23,7 @@ jobs:
           python-version: '3.10'
 
       - name: Cache pip
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # this path is specific to Ubuntu
           path: ~/.cache/pip

.github/workflows/gh-pages.yml

@@ -22,7 +22,7 @@ jobs:
           python-version: '3.10'
 
       - name: Cache pip
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # this path is specific to Ubuntu
           path: ~/.cache/pip

.github/workflows/isort.yml

@@ -23,7 +23,7 @@ jobs:
           python-version: '3.10'
 
       - name: Cache pip
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # this path is specific to Ubuntu
           path: ~/.cache/pip

.github/workflows/pylint.yml

@@ -23,7 +23,7 @@ jobs:
           python-version: '3.10'
 
       - name: Cache pip
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # this path is specific to Ubuntu
           path: ~/.cache/pip

.github/workflows/pytest.yml

@@ -27,7 +27,7 @@ jobs:
           python-version: ${{ matrix.python-version }}
 
       - name: Cache pip
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # this path is specific to Ubuntu
           path: ~/.cache/pip

.github/workflows/regtest.yml

@@ -27,7 +27,7 @@ jobs:
           python-version: ${{ matrix.python-version }}
 
       - name: Cache pip
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           # this path is specific to Ubuntu
           path: ~/.cache/pip